Paper making apparatus



March 3, 1942. J. A. SPENCER I PAPER MAKING'APPARATUS Filed June 22, 1939 INVENTOR.

ATTORNEY.

Patented Mar. 1942 v paras t m s'ra'rss- PATENT scan a. Spencer, some mam-ah, signor to Spencer Specialties Inc, South i Fr es APPTUS icy Falls, a corporation of Massacht Application June as, 1939; Serial No. 280,592

determined relationship to the surface speed of the paper-m 1 1. element such as the Fourdrinier wire. It is thereby possible to obtain the desired formation of the p per and watermark.

According to prior practice in the paper making art the dandy roll has been mounted at its ends and on top of the Fourdrinier wire for free rotation so that it rests on and is driven by the paper being formed on the wire.

This prior practice has numerous and serious objections and disadvantages. .More particularly the dandy lags to some extent relative to the Fourdrinier wire due to slippage so that the formation of the paper is not as uniform as is'desired and where water-marking devices are used on the dandy the watermark in thepaper is more or less blurred and indistinct. Also in many cases the speed of the paper machine is necessarily reduced to some extent inorder to reduce as far as possible the lag or slippage to an operable condition. y

Because the dandy is rotated by reason of its contact with the paper being formed on the wire and is not positively driven the lag orslippage occurs and this causes a mound or wave of water and paper making fibers to be'built up ahead of the dandy. There is in effect an excess of water and fibers ahead of the dandy because the dandy operates somewhat after the manner of a dam against the paper making material ci. oz-ss) ing up of a wave or mound ahead of the dandy and greatly improving the formation of the paper as well as providing a distinct non-blurred watermark where used.

Preferably, according to this invention, the surface speed of the dandy will be .definitely related to and slightly greater than that ofthe wire as distinguished from the relatively less and non-uniform dandy speed of the prior art. To accomplish this means is provided to drive the dandy at a predetermined speed relative to. I that of the wire and to vary the speed thereof in synchronism with variations in the increase or decrease in the speed of the wire all to the end thatthe dandy operates at all times at a speed having a predetermined relation to that of the wire. Various other novel objects and advantages of f the invention will be observed from the following I stands 8 which may be supported in the usual description of the preferred form thereof, reference being had to the drawing, wherein:

Fig. 1 is a side elevationaldiagrammatic view showing" a portion of apaper-making machine with the dandy operating mechanism of the invention associatedtherewith; and

Fig. 2 is a detail end elevational view show an end of a dandy with operating connections therefor.

Referring now to the drawing more in detail,

the invention will be fully described.

A dandy rollis indicated by 2 which has the opposite ends 4 of its shaft rotatablycarried in manner on rails 8. The paper-making element or Fourdrinier is represented by It and upper and lower couch rolls are represented by I! and l4, there 'being one or more suction boxes indibeing carried along by the wire. The excess wasary to limit the speed of the wire to a which will 'best accommodate the undesirable conditions.

According to this invention the dandy roll is positively driven or rotated from some positively 1 driven element of the paper machine so that its surface speed may a predetermined relation to that of the wire, thereby eliminating the build- 58 cated by I.

According to the inventionthe operating mechanism of the invention is driven from some part of the paper machine which operates in synchronism with the wire so that when the wire speed increases or decreases the speed of the dandy is increased or decrease in synchronism' therewith.

Accordingly for purposes of disclosure the shaft 20 of the lower couch roll carries a sprocket 22 which is operatively connected as by a chain 24 to a sprocket 35 on the shaft of a frequency changer or alternator 28. The latter may be 0 the 220 volt three-phase type. j

The unit 28 will be positively driven by and from the couch roll and accordingly as the speed thereof increases or decreases the speed of the unit is increased or decreased. Y

, an output shaft 38. This unit will be of the well known type including gearing or sprockets and chains toprovide a speeddifierential between the shafts 36 and 38 with adjusting means op erable by an adjusting member 40 to vary the ratio or differential of speeds of shafts 88 and 38.

A sprocket 42 is provided on shaft 38 of the unit 3% and a chain 48 around said sprocket 42 engages a sprocket 48 of a shaft 50 joumalied in a bracket 52.

The shaft 50 is somewhat loosely coupled to I the end ii of the dandy shaft by a coupling, as shown, in Fig. 2 to permit slight movements of the dandy relative to shaft 50 and tofacilitate the dandy to be set on or removed from the machine or its replacement by another.

The unit 54 is adjusted to provide the desired differential speed between the dandy and the wire. According to the invention the surface speed of the dandy is preferably slightly in excess of that of the wire in order to eliminate the wave of water and fibers ahead of the dandy as in the prior practice and thereby obtain the desired formation of paper and watermark.

It has been found that when the speed of the dandy is in excess of the wire in the neighborhood of 2 to 4% that new and very desirable results are obtained and to obtain the desired differential the unit 34 is adjusted.

The unit 28 is operated directly from such an element as the couch roll so that the speed thereof varies accordingly as that of the wire varies and said unit 28 feeding the motor 80 directly has its speed vary in synchronism with that of the wire. Thus by adiusting the unit 34 to provide a desired predetermined diflerential of speed between the dandy and wire, should the wire speed decrease or increase the predetermined reiative speed of the dandy and wire may be maintained.

An overrunning clutch 44 on shaft 50 may be provided and this may be of any well known type known in the art. Said clutch will be so constructed and arranged that sprocket 48 rotates the dandy shaft but should anything happen to the dandy drive the wire may rotate the dandy.

While I have described the invention in great detail and with respect to the present preferred form thereof, it is not desired to be limited thereto since changes and modifications maybe made therein without departing from the spirit and scope of the invention. The invention may be embodied in other specific forms without departing from the essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What it is desired to claim and secure by Letters Patent of the United States is:

1. The combination of the Fourdrinier wire, dandy roll thereover having a shaft rotatably supported, and a positively driven member rotatable in synchronism with said wire of a paper making machine with means for driving said dandy roll from said member comprising, drive means including a drive shaft journalled for rotation in substantial alignment with said dandy roll shaft, a. drive unit including change speed mechanism and output and input shafts, operative connections between said output shaft and said drive shaft, electrical apparatus having an output shaft connected to said input shaft of the unit and an input shaft, and operable connections between said rotatable member and the input shaft of said electrical apparatus, all adapted and arranged whereby said dandy roll is rotated in synchronism with the wire at all of its speeds.

2. The combination of the Fourdrinier wire, dandy roll-thereover having a shaft rotatably supported, and a positively driven member rotatable in synchronism with said wire of a paper making machine with means for driving said dandy roll from said member comprising, drive means including a drive shaft journalled for rotation in substantial alignment with said dandy roll shaft, a drive unit including change speed mechanism and output and input shafts, operative connections between saidoutput shaft and said drive shaft, electrical apparatus having an output shaft connected to said input shaft of the unit and an input shaft, and operable connections between said rotatable member and the input shaft of said electrical apparatus, all adapted and arranged whereby said dandy roll is rotated in synchronism with the wire at all of its speeds. said drive means including a clutch whereby said dandy roll may rotate in one direction independently of said drive unit, all adapted and arranged whereby said dandy roll is rotated in synchronism with the wire at all of its speeds.

3. The combination of the Fourdrinier wire, dandy roll thereover having a shaft rotatably supported, and a positively driven member rotatable in synchronism with said wire of a paper making machine with means for driving said dandy roll from said member comprising, drive means including a drive shaft iournalled for rotation in substantial alignment with said dandy roll shaft, a drive unit including change speed mechanism and output and input shafts, operative connections between said output shaft and said drive shaft, electrical apparatus including electrically connected motor and generator each having a shaft, the shaft of the motor operabiy connected to the input shaft of said unit and the shaft ofthe generator operably connected to the rotatable member of the paper machine, all adapted and arranged whereby said dandy roll may be rotated from said rotatable member at a surface speed greater than that of the wire and in synchronism therewith.

JOHN A. SPENCER. 

